In an extraordinary defence of the long running investigation, Mike Veale, the Chief Constable of Wiltshire Police, denied it was a "witch-hunt" and said he would not "buckle" under mounting pressure to bring the £700,000 inquiry to a close.

In a three page statement, Mr Veale said the force was "duty bound" to investigate the complaints even though Sir Edward has been dead for more than a decade.

British Conservative prime minister Edward Heath with the American Secretary of State, Henry KissingerCredit:
Leonard Burt

He suggested that the inquiry was even more important because of Sir Edward's prominent position, but admitted that many of the allegations had been made against other people.

Defending Operation Conifer, which has been running for 18-months, he quoted College of Police national guidelines and said: "It is clear that I am expected to conduct a proportionate investigation which will result in a distinct outcome or report, and the closer the suspect is to the state the greater the obligation and the more probing the investigation should be."

The statement has prompted fears that Sir Edward's reputation may never be fully restored even if there is no evidence against him.

At the conclusion of the investigation a confidential closing report will be written...and at that time I will take advice as to what I can legally put in the public domainThe statement

Mr Veale has faced intense criticism over Operation Conifer, which was launched when Wiltshire Police made a televised appeal outside Sir Edward's former home, Arundells, in which they asked for "victims" to come forward.

Despite this unusual approach, Mr Veale denied that the investigation was a "fishing" exercise and stressed it was the police's role to investigate allegations "without fear or favour and go where the evidence takes us".

But a similar approach by the Metropolitan Police during its ill fated Operation Midland investigation into claims of a VIP paedophile ring at the heart of Westminster, led to severe criticism.

Mr Veale insisted that a "significant" number of people had made allegations of abuse, but he refused to disclose how many, stressing that it remained a "live inquiry".

Last week it emerged that some of the allegations made were about satanic abuse rituals in the Wiltshire area, but Mr Veale said they did not involve Sir Edward.

In a further defence of the probe he added: "This investigation may contribute to a wider picture of truth-seeking and reconciliation relating to non-recent child abuse allegations involving institution settings."

Last night Sir Edward's godson, Lincoln Seligman said: " The police have hinted recently that Conifer has become an investigation into people other than Edward Heath. But they have allowed the public to continue to believe that their main interest is in Edward Heath. But if they have uncovered no evidence against him after eighteen months ,and costs of £700,000 , they should say so.

"And if Conifer is wound up he deserves to be exonerated as publicly as he was initially smeared. Shuffling the inquiry's findings off into the night is not acceptable. "

Harvey Proctor, who endured more than a year under a cloud of suspicion after being falsely accused of abuse as part of Operation Midland said it was time to split the investigation up.

He said: "The police have taken leave of their senses and are acting politically rather than in a proper British police tradition."

He added: "Wiltshire Police should immediately divide the two parts to the investigation - that part concerning Heath and the strand relating to others.

"Mike Veale is reducing Heath's name by making smoke in one part of the investigation which may have no relevance to the other part relating to Sir Edward."